1. Technical Field
The present invention is directed toward window operators, and more particularly toward window operators for opening and closing French casement windows.
2. Background Art
Casement windows are well known in the art. Such windows include a window sash mounted within a window frame with top and bottom hinge structures securing the sash within the frame for opening outwardly by generally pivoting about one side of the sash. More specifically, a typical bottom hinge includes a sash arm fixed to the top of the sash and pivotally secured at one end to a sliding shoe. The shoe is guided in its sliding movement by a track extending along the bottom of the window frame. A support arm completes the linkage of the hinge, and is typically pivoted at opposite ends to the sash arm and the track. Such hinges are shown, for example, in U.S. Pat. Nos. 4,593,431 (Re. 32,846) and 5,040,267. Other variations of such hinges are also shown, for example, in U.S. Pat. Nos. 3,838,537, 4,674,149, 4,726,092, 5,083,344, and 5,093,960.
Operators controlling movement of such casement windows are also well known. Various such operators are shown, for example, in U.S. Pat. Nos. 4,241,541, 4,253,276, 4,266,371, 4,305,228, 4,346,372, 4,497,135 4,823,508, 4,840,075, 4,932,695, 4,937,976 and 5,054,239.
French casement windows have two different window sashes within a single frame, each sash supported for movement by hinges such as described above by generally pivoting about their outer vertical sides (adjacent the frame) with the window sashes meeting in the middle of the frame when closed. Frequently, such windows include a fixed mullion in the middle of the frame, with the middle vertical sides of the sashes seating against the mullion to ensure a suitable seal against weather, rain, etc. where the French casement windows meet one another.
It is, however, desirable to maximize the opening through the frame when the sashes are open, not only for aesthetics (maximizing the view and open feel of the window) but also to allow egress through the window in emergency situations. In order to provide these advantages, it is necessary to avoid all obstacles from the middle of the frame, specifically, the above described mullion used in other such windows. However, in such windows it is necessary to overlap the two sashes in the center of the frame in order to ensure that a suitable closure seal is provided.
Of course, as with other casement windows, it is often desirable to provide operators to ease their opening and closing. Typically, two operators are provided with such windows, one for each sash. Such a structure is, of course, inconvenient in that it requires that two different operators be manipulated in order to fully open the window. Further, dual operator structures are not readily usable with French casement windows which do not have a center mullion, since the overlap in the sashes in such windows would result in damage to the window sashes and/or window operators if a person attempted to open or close the wrong sash first.
The present invention is directed toward overcoming one or more of the problems set forth above.